Methods: We studied 90 women with uncomplicated pregnancies undergoing elective caesarean section under spinal anaesthesia. Intravenous access was established in all with two peripheral intravenous lines, the first being used for the baseline volume infusion. Immediately after induction of spinal anaesthesia, Lactated Ringer's solution (Group L) or HES (Group C) infusions were started at the maximal possible rate via the second line in groups L and C respectively. The third group (Group E) patients received lactated Ringer's solution at a 'keep vein open' rate to maintain the double-blind nature. The incidence of hypotension, ephedrine requirements, total amount of volume and side effects were recorded.